The rate of influx and efflux of glycerol in cells in tissue culture and in intact tissues and organs will be explored in order to design perfusion protocols for introduction and removal of glycerol from organs. Freezing experiments will be conducted on tissues in situ in experimental animals in order to take advantage of ideal post-thaw perfusion. Tissues will be frozen both without cryoprotection and following isolation of the tissues and perfusion with glycerol.